hang - you're getting tons of good info. Overwhelming, isn't it?
My GF has a 12 year old son we've taken a couple times in the last year, and he's been going since he was 5.
If you want to splurge on one meal - NO question - eat at the tallest place, best views in Vegas, "Top O' the World" at the Stratosphere - 105 stories up - it slowly rotates 360. The views are THE most amazing on the strip without a chopper and the food is seriously good. One story up they'll strap you in and toss you down 100 stories so you can vomit it out, lol. Paris is also a great place to eat for the experience.
Circus isn't top of line amusement park, but is still a blast for the right age. Good rides. Took my 12 yr old for his 1st coaster - he was white knuckled, bought the pic of it.
Rode ride after ride for hours on end, til he was almost sick. Price is right.
On the free, after nightfall if you want to stroll - Treasure Island is next door to Mirage. Free pirate shows and powerful volcanoes (on the hour, sharp). Mirage has a decent "Zoo" with white lions, dolphins, caged pool players eating peanuts
++ for @ $14 (day time only). Nice lobby aquarium (my friend built it, lol).
Freemont St is mesmerizing at night. Perhaps to a 13 year old the most mesmerizing stroll - SO MUCH sensory titalation. Blaring fun music, blinding lights, zip lines overhead, shops, funnel cakes type food, young girls. He'll love it.
Venetian Canal ride is not free, and may or may not get a rise out of your son. It's more adult oriented at the entire incredible Venetian Resort. But walk through it, it's perhaps the most oppulent resort there - think Michelangelo on steroids with 80,000 tons of gold leaf to burn.
We expect a full report in the morning! Enjoy!